Dust-preventer attachment for rotary pulverizers.



(Application filed June 8, 1899.)

(No Model.)

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UNITED STATES PATENT OFFICE.

JACOB KULLMAN, OF BENICIA, CALIFORNIA.

DUST-PREVENTER ATTACHMENT FOR ROTARY PULVERIZERS.

SPECIFICATION forming part of Letters Patent No. 642,747, dated February 6, 1900.

Application filed June 8, 1899- Serial No. 719,811. (No model.)

To all whom, it may concern:

Be it known that I, JACOB KULLMAN, a citizen of the United States, residing at Benicia, county of Solano, State of California, have invented an Improvement in Dust-Preventer Attachments for Rotary Pulverizers; and I hereby declare the following to be a full, clear, and exact description of the same.

My invention relates to an attachment for preventing the escape of dust from apparatus which is designed for crushing and pulverizing barliI-Qeones, brick, or other like material.

It consisss of the attachment which I will hereinafter describe and claim.

Referring to the accompanying drawings, Figure 1 illustrates one form of machine to which my attachment is applied. Fig. 2 is a perspective view of the attachment detached.

In apparatus for crushing and pulverizing various materials in which the rapidly-revolvin g heaters act against the material and throw it outwardly against circumferentially-arranged bars fixed within the case and surrounding the beaters great diflicnlty is experienced by reason of the escape of the dust produced by the pulverizing and its discharge through the opening which is necessary for feeding the material into'the machine. This is especially noticeable in bark-pulverizers,

where a large proportion of the bark is reduced to a dust before being discharged from the machine. The present device effectually prevents the escape of this dust except through the usual discharge-opening at the bottom.

A is the case within which the heaters 13 rotate, these heaters being mounted upon a shaft, and O are the inclosing bars fixed transversely across the machine exterior to theline of rotation of the heaters, so that bark introduced into the machine will be pulverized by the action of these heaters.

D is the feed-opening through which the bark is introduced into the machine to be acted upon by the heaters and the pulverized material is discharged through the bottom of the machine.

E' is a hollow attachment or structure holt ed to the outside of the cover just above the feed-opening and extending across from one side to the other of the case approximately the full width thereof. Through the side of the case and opening into this hollow structure are a considerable number of holes F,

which may be ofany suitable size. I have made them about three-fourths of an inch in diameter and find this size very satisfactory. The size of the hollow structure which is fixed upon the outside of the case maybe approximately ten inches in depth and extend about the same distance along the curvature of the case, the length, as before stated, being about equal to the width of the case. This is sufficient for a machine having the interior of the case three to four feet in diameter. The actual effect of this addition is to prevent the dust from being thrown out through the feedopening; but the dust does not collect within the structure to any extent, nor is there any discharge or exhaust opening from it. It is simply a hollow inclosure connecting by the holes with the interior of the case. It is an attachmentwhich may be applied to the usual form of rotary pulverizer without change in the latter, except as to the formation of the holes F. It has closed sides and ends, and its base is curved to conform to the cover of the machine and is flanged to make a close fit and to enable it to be bolted directly on the outside of the cover of the machine without difficulty and at little expense. When placed in position,as before indicated,the escape of dust from the feed-opening of the machine is prevented, while the absence of the attachment from the machine results in the room in which the machine is operating being so filled with dust driven out of the feed-opening as to cause serious inconvenience to the operators.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. An attachment for a rotary pulverizer, said attachment open at the bottom and formed with a curved bottom edge adapted to be fitted and secured to the curved top or cover of the pulverizer.

'2. An attachment for a rotary pulverizer, said attachment formed with open bottom and imperforate top and sides and having a concave flanged bottom edge or base adapted to he bolted to the convex top or cover of the casing of the pulverizer.

In witness whereof I have hereunto set my hand.

J. KULLMAN. Witnesses:

W. E. RULOFSON, D. M. HURLY. 

